Rotary cutting machines, particularly relatively large ones, are used in various applications which include, but are not limited to, felling trees and other natural plant growth in the forestry industry, clearing brush, grinding tree stumps, cutting rock and/or earth in the mining and construction industries, cutting up items such as used tires and other man-made products in various industrial applications, and shredding or grinding all manner of materials, both natural and man-made, such as wood, waste, plastic, metals, rubber, etc. Relatively smaller rotary cutting machines, such as small circular saws for example, are further used in countless other smaller-scale applications, from home renovation to commercial applications, such as construction, forestry and the like. Depending on the type of circular saw, the central disk of the saw either rotates (for the smaller circular saws) or remains rotationally fixed but has teeth on linked holders which rotate about the periphery of the saw disk, much as per chain saws.
For rotating cutting machines which are used as brush cutters or brush mowers (i.e. for clearing relatively small trees, bushes, brush, etc.), a rotating cylindrical drum has several rows of cutting teeth disposed longitudinally along the drum at circumferentially spaced apart intervals. Such rotating drums are typically mounted to the end of a boom or articulated arm, such as to permit the manipulation of the rotating brush mower.
Regardless of the type of rotating cutting machine, a plurality of cutting teeth rotate, whether independently about the periphery of the rotationally-stationary disk/drum/shaft, or together with the rotating disk/drum/shaft when fixed thereto, in order to cut into the workpiece material to be cut.
Particularly with known saw teeth used on large circular saws, such as those used for felling trees or cutting through large volumes of man-made materials, and on large scale brush mowers, each saw tooth may be removable from its associated holder (mounted to the disk or drum) such that it is replaceable. Each of these saw teeth can include several separate cutting edges thereon. Thus, when one cutting edge wears or becomes damaged and thus unsuitable for cutting, i.e. optimum cutting, the tooth in question can be removed from the holder and replaced back in place thereon with a different cutting edge in position for contacting the workpiece. Once all the cutting edges on any saw tooth have been used, the tooth can be removed from the holder and either replaced with a new tooth or repaired and/or sharpened and replaced back in position.
Some such removable saw teeth and their associated holders are described in the following U.S. patents, the entire contents of which are incorporated herein by reference: U.S. Pat. No. 5,205,199 issued on Apr. 27, 1993, U.S. Pat. No. 5,303,752 issued on Apr. 19, 1994, U.S. Pat. No. 5,307,719 issued on May 3, 1994 and U.S. Pat. No. 5,664,965 issued on Jul. 8, 1997, all to Charles D. MacLennan. Typically, such saw teeth include up to four cutting edges on a front face of the tooth, and have a flat rear face, opposite said front face, which abuts with a corresponding surface on the holder against which the tooth is fastened in engagement.